chain guide ripped off?

I just installed a 52 tooth rear sprocket and a new pro taper 520 series chain onto my 2006 yz250, everything seemed to be in good shape on the stand, no binding.  I took it for a test ride and after a few laps I heard a pop and thought my chain broke, it didn't but the chain guide welded to the rear swing arm broke at every weld place!! It was just dangling there with the chain running through it, mounting bracket still bolted to it lol. Has anyone ever had this happen? any thoughts on what may have caused this?  I didn't even touch the chain guide, only removed the rear wheel and installed a new sprocket and lined my axle back up.  I could squeeze three fingers between the chain and top of the swing arm when the bike was on the stand, so it couldn't have been too tight...

IT happened to me last year, the welds werent realy burtnt into the swingarm and mine simply peeled off. You couldnt even tell where it was welded to the swingarm.

Did you have yours welded back? I wonder there is a different kind I chain guide I need to get for the bigger 52 tooth sprocket.. Was thinking of jb welding the bracket back on, think that would hold?

I have had it happen a few times, its the poor welding from the factory, every Yz I have owned since the last break I have had welded by a good aluminum welder and have had no problems

Did you have yours welded back? I wonder there is a different kind I chain guide I need to get for the bigger 52 tooth sprocket.. Was thinking of jb welding the bracket back on, think that would hold?

DO NOT TRY THAT.... The chain guide can run around the rear sprocket under the chain and break all kinds of things. Mine broke the hub. I just had mine welded back on.

Ok thanks, I will have it welded and replace the chain guide with a tw designs one. I heard they were good

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